NOTE: As their name suggests hints are not exactly Dungeonland cheats, and are usually just simple (but very useful) tips on how you can unlock secret level, features, find hidden areas and such. Hopefully these will make playing Dungeonland even more entertaining.

Steam Achievements
A Cake Made of Pain: Complete the Tutorial
A Matter of Hygiene: Kill 50 Heroes as the Dungeon Master
A Taste Of The Dark Side: Your first DM unlock
Bar Fight: Defeat The Beer Holder on Harder difficulty
Board of Directors: Unlock all DM Bosses
Card Advantage: Use Ace Up The Sleeve to draw an Ace Up The Sleeve card
Challenge Accepted: Complete a level with at least one active Challenge
Commander Shepherd: Kill 5 enemies with a single sheep
Crowded Control: Trap all Heroes inside a single Trapping Walls spell
Don't Step On The Grass: Defeat The Lumber Tree on Hard difficulty
Drunken Haze: Defeat The Beer Holder on Hard difficulty
Dungeon(Land) Master: 100% Game Completion. We bow down to your awesomeness.
Elder Abuse: Defeat The Elder Dragon on Hard difficulty
First Blood: Kill your first Hero as the Dungeon Master
Friend Sheep: Complete a level with no sheep harmed
Frozen Fool: Kill a Hero affected by your Evil Freeze ability
Glory and Justice: Complete all Dungeons as Warrior
Gold Fever: Earn 100,000 lifetime Gold
He Saw, We Conquered: Defeat The Lumber Tree on Harder difficulty
He Still Got Some Tricks On Him: Defeat The Elder Dragon on Harder difficulty
Here's Your Reward: Have a Hero open your Mana MimicHerocide: Kill 300 Heroes as the Dungeon Master
Knock on Wood: Defeat The Lumber Tree on Impossible difficulty
Monster Breeder: Unlock all DM Monsters
Monster Master: Unlock all DM Special Monsters
My First Loot: Earn 5,000 lifetime Gold
Old Schooled: Defeat The Elder Dragon on Impossible difficulty
Park Regular: Play for 6 hours
Phenomenal Cosmic Powers: Complete all Dungeons as Mage
Someone Got Stabbed: Complete all Dungeons as Rogue
The Power Of Evil: Win a DM Mode match as the Dungeon Master
The Power Of Friendship: Win a DM Mode match as a Hero
Tough Love: Kill a friend. We know it was an accident... right?
Versed In Evil: Unlock all DM Traits
Warlock: Unlock all DM Spells
Watch This: Defeat The Beer Holder on Impossible difficulty
Watch Your Step (Or Not): Have a Hero activate one of your traps while using Stealth Traps
Who spilled these Heroes all over my floor?: Wipe out the Hero party with a Boss monster
Window Shopper: Buy an item on the store
With My Own Hands: Unlock all DM Possession Abilities
You Want Something Done Right: Kill a Hero with a Possessed monster